JP2021100758A - Oil-and-fat containing wastewater treatment method, system and apparatus - Google Patents

Abstract

To provide oil-and-fat containing wastewater treatment methods which effectively reduce a concentration of oil-and-fat in wastewater which continuously flows in and out and includes miscellaneous microbes, using a microbial preparation having oil and fat degradation capability, and related systems and devices.SOLUTION: The present disclosure provides oil-and-fat containing wastewater treatment methods, and related systems and devices, including a process of continuously or intermittently feeding a microbial preparation having an oil-and-fat degrading capability into an oil-and-fat degrading tank which oil-and-fat containing wastewater continuously flows in and out of, and degrading the oil-and-fat, in which an amount of the fed microbial preparation is the amount that enables microbes to settle in the oil-and-fat degrading tank, and in which microbes other than those contained in the microbial preparation are present in the oil-and-fat containing wastewater.SELECTED DRAWING: None

Description

The present invention relates to a fat-containing wastewater treatment method using a microbial preparation capable of decomposing fats and oils, and related systems and devices.

Decomposition of fats and oils by microorganisms is used for wastewater treatment. A large amount of oil contained in wastewater from food factories and oil refining factories may greatly reduce the treatment efficiency of various wastewater treatment processes such as activated sludge treatment, membrane separation activated sludge method (MBR), and anaerobic digestion. Therefore, many factories that discharge such wastewater install a pressurized flotation separation device or the like as a pretreatment for these treatment processes.

The pressurized levitation separation device removes oil by solid-liquid separation, but (1) a large amount of recovered oily sludge must be treated as industrial waste, and (2) a large amount of flocculant is used to levitate the oil. It is necessary to send air bubbles to give buoyancy by aeration as well as to use it. (3) It may be necessary to install a deodorizing device in factories that are a source of foul odors and are close to residential areas. In addition, since it is easily affected by fluctuations in oil content, it takes labor for operation management. (5) As a result, there are problems such as high costs for industrial waste treatment, operation, management, maintenance, etc. ..

Therefore, there is an urgent need to establish a technology that eliminates oil in wastewater without separating it. Under these circumstances, the application of oil and fat decomposition technology by microorganisms has been attempted.

Therefore, the present inventor has reported a novel microorganism Burkholderia arboris SL1B1 strain that secretes lipase, which is a fat hydrolase, as a microorganism that efficiently treats fat-containing wastewater (Patent Document). 1). Furthermore, it was reported that fats and oils were efficiently decomposed by using the Berkholderia arboris in combination with a microorganism that decomposes glycerol, which is a hydrolysis product of lipase (for example, Candida cylindrasea). (Patent Document 2, Non-Patent Document 1). It has also been reported that fats and oils can be efficiently decomposed by using Burkholderia alboris in combination with Yarrowia lipolytica, which does not produce lipase but decomposes free fatty acids (patented). Document 3). With this oil / fat decomposition ability, it is possible to replace the pressurized flotation separation device.

However, no matter how high the decomposition ability of the microbial preparation is used, the desired effect cannot be obtained unless the usage is correct. In fact, microorganisms that have been shown to be degradable in the laboratory often become ineffective when used in the field. The main reason is that the conditions in the laboratory and the conditions in the actual field are very different. In the laboratory, in many cases, only the target microorganism is inoculated and cultured in a sterile closed system. In addition, many cultures are performed in batches. Results are quite different for batch and continuous reactions. Therefore, a continuous reaction may be carried out in the laboratory as well. However, at many sites, the inflow and outflow of wastewater into the fat decomposition tank is continuous, while the addition of microbial preparations is not continuous but intermittent. In that case, the conventional operational theory of continuous reactors does not hold.

In addition, since wastewater treatment is performed in an open system, it is an environment in which innumerable miscellaneous microorganisms exist in addition to input microorganisms, and target microorganisms such as fat-decomposing microorganisms are stably established in such a microbial community. There is no methodology for (a state in which the target microorganism exists effectively without being culled in the target environment). In addition, since the wastewater continuously flows out with a constant residence time, if the target input microorganism cannot overcome the survival competition with innumerable other microorganisms and grow at a specific growth rate faster than the residence time, it will be washed out. It will be. Therefore, the expected decomposition effect is often not obtained, which is an issue in the field of environmental biotechnology.

As a method of avoiding washout, there is a method of fixing microorganisms on the carrier, but in addition to the problem that the oil adheres to the carrier in the wastewater with a lot of oil, new waste called the carrier is generated and the carrier is affected. New issues such as cost arise.

Furthermore, until now, little attention has been paid to how to use the microbial preparation, and in most cases, the input amount and the input interval are sensuously adjusted while observing the effect. In fact, it was difficult to establish a uniform methodology because the amount of wastewater and the concentration of fats and oils in the wastewater vary depending on the site. In addition, there is a problem that it is difficult to apply the same microbial preparation to a wide range of fat and oil concentrations in the prior art. In particular, applying the microbial formulation for high concentrations of oil discharged like from food factories and oil refineries is difficult, even applicable, high levels of microorganisms concentration of more than 10 ⁹ cells / mL is necessary.

JP-A-2010-227858 Japanese Unexamined Patent Publication No. 2010-2278849 Japanese Unexamined Patent Publication No. 2013-146689

Journal of Bioscience and Biotechnology, Vol. 107, No. 4,401-408,2009

The present invention uses a microbial preparation capable of decomposing fats and oils to continuously flow in and out, and effectively reduces the concentration of fats and oils in wastewater in which miscellaneous microorganisms are present. Provide the device.

As a result of intensive research to achieve the above object, the present inventor is fundamentally different from the conventional continuous culture when the microbial preparation is put into the fat decomposition tank in which the fat-containing wastewater continuously flows in and out. It was found that the introduced microorganisms do not necessarily have to grow in the fat / oil decomposition tank, and that the fats and oils can be decomposed if they are present in a certain number or more.

The present invention has been completed by further studying based on these findings, and provides the following oil-containing wastewater treatment method, and related systems and devices.
Item A1. It is a step of continuously or intermittently adding a microbial preparation having an oil / fat decomposition ability into an oil / fat decomposition tank into which the oil / fat-containing wastewater continuously flows in and out to decompose the oil / fat. Is an amount effective for colonizing the fat / oil decomposition tank, and the fat / oil-containing wastewater contains microorganisms other than the microorganisms contained in the microbial preparation, which comprises a step of treating the fat / oil-containing wastewater.
Item A2. Item 6. The treatment method according to Item A1, wherein the oil / fat decomposition tank does not contain a carrier.
Item A3. Item 2. The treatment method according to Item A1 or 2, wherein the microbial preparation comprises at least one microorganism selected from the group consisting of a microorganism that produces lipase and a microorganism that decomposes fatty acids and / or glycerol.
Item A4. The microbial preparations include Bacillus bacterium, Corinebacterium bacterium, Rhodococcus bacterium, Burkholderia bacterium, Asinetobacter bacterium, Pseudomonas bacterium, Alkalinegenes bacterium, Rhodobacter bacterium, Larstonia bacterium, Acidborax bacterium. Items A1 to 3, which include at least one microorganism selected from the group consisting of Seratia bacterium, Flavobacterium bacterium, Candida yeast, Yarrowia yeast, Cryptococcus yeast, Tricosporone bacterium, and Hansenula bacterium. The processing method according to any one of the above.
Item A5. Item 8. The treatment method according to any one of Items A1 to 4, wherein the waste water contains fats and oils having a concentration of 300 mg / L or more of the normal hexane extract on average.
Item A6. Item 2. The item according to any one of Items A1 to 5, wherein the input amount of the microbial preparation is 5.0 × 10 ^{4 to} 1.0 × 10 ^{7 cells / mL with respect to the wastewater in the oil / fat decomposition tank.} Processing method.
Item A7. Items A1 ^{to 6, wherein the input amount of the microbial preparation is 3.0 × 10 4 to} 1.0 × 10 ⁸ cells per 1 mg of the normal hexane extract in the oil / fat-containing wastewater flowing into the oil / fat decomposition tank. The processing method described in item 1.
Item A8. Item 2. The treatment according to Item A7 ^{, wherein the input amount of the microbial preparation is 3.0 × 10 4 to} 1.0 × 10 ⁷ cells per 1 mg of the normal hexane extract in the oil / fat-containing wastewater flowing into the oil / fat decomposition tank. Method.
Item A9. Item 8. The treatment method according to any one of Items A1 to 8, wherein the dissolved oxygen concentration of the oil-and-fat-containing wastewater in the oil-and-fat decomposition tank is 0.05 mg / L or more.
Item A10. Item 8. The treatment method according to any one of Items A1 to 9, wherein the pH of the oil-containing wastewater in the oil-fat decomposition tank is in the range of 4.5 to 9.0.
Item A11. Item 8. The treatment method according to any one of Items A1 to 10, wherein the temperature of the oil-containing wastewater in the oil-fat decomposition tank is in the range of 12 to 42 ° C.
Item A12. Item 8. The treatment method according to any one of Items A1 to 11, wherein the hydraulic residence time (HRT) of the oil / fat decomposition tank is 1 hour or more.
Item A13. Item 6. The treatment method according to any one of Items A1 to 12, wherein the HRT of the oil / fat decomposition tank is 12 hours or more and 48 hours or less.
Item A14. Item 8. The treatment method according to any one of Items A1 to 13, wherein the C / N of the oil-containing wastewater in the oil-fat decomposition tank is in the range of 2 to 50.
Item A15. Item 8. The treatment method according to any one of Items A1 to 14, wherein the N / P of the oil-containing wastewater in the oil-and-fat decomposition tank is in the range of 1 to 20.
Item A16. Item 8. The treatment method according to any one of Items A1 to 15, wherein the amount of microorganisms input into the effluent from the oil / fat decomposition tank is 1 × 10 ^{8 cells / mL or less.}
Item A17. Item 2. The treatment method according to any one of Items A1 to 16, wherein the concentration of the input microorganisms in the effluent from the fat decomposition tank is 100 times or less the concentration of the input microorganisms charged into the oil / fat decomposition tank.
Item A18. Item 2. The treatment method according to Item A17, wherein the concentration of the input microorganisms in the effluent from the oil / fat decomposition tank is 0.1 to 10 times the concentration of the input microorganisms charged into the oil / fat decomposition tank.
Item A19. A fat decomposition tank for treating wastewater containing fats and oils.
Oil decomposition tank and
With a blower
An oil / fat decomposition tank including a sensor for detecting a dissolved oxygen concentration, a temperature, and a pH in the oil / fat-containing wastewater in the oil / fat decomposition tank.
Item A20. A system for use in the treatment method according to any one of items A1 to 18, comprising the oil / fat decomposition tank according to item A19.
Item A21. Item 2. The system according to item A20.
The storage tank for the microbial preparation and
The amplification tank of the microbial preparation and
The system is configured such that the microbial preparation amplified in the amplification tank is charged into the oil / fat decomposition tank.
Item A22. The system according to item A21, further comprising an execution / control unit that controls or executes one or more of the steps in the processing method according to any one of items A1 to 18.
Item B1. It is a step of continuously or intermittently adding a microbial preparation having an oil / fat decomposition ability into an oil / fat decomposition tank into which the oil / fat-containing wastewater continuously flows in and out to decompose the oil / fat. Is an amount that can be fixed in the fat / oil decomposition tank, and the fat / oil-containing wastewater contains microorganisms other than the microorganisms contained in the microbial preparation, which comprises a step of treating the fat / oil-containing wastewater.
Item B2. Item 6. The treatment method according to Item B1, wherein the microbial preparation comprises at least one microorganism selected from the group consisting of a microorganism that produces lipase and a microorganism that decomposes fatty acids and / or glycerol.
Item B3. The microbial preparations include Bacillus bacterium, Corinebacterium bacterium, Rhodococcus bacterium, Burkholderia bacterium, Asinetobacter bacterium, Pseudomonas bacterium, Alkalinegenes bacterium, Rhodobacter bacterium, Larstonia bacterium, Acidborax bacterium. Item B 1 or, which comprises at least one microorganism selected from the group consisting of Seratia bacterium, Flavobacterium bacterium, Candida yeast, Yarrowia yeast, Cryptococcus yeast, Tricosporone bacterium, and Hansenula bacterium. The processing method according to 2.
Item B4. Item 2. The treatment method according to any one of Items B1 to 3, wherein the amount of the microbial preparation to be added is 5.0 × 10 ^{4 to} 1.0 × 10 ^{7 cells / mL with respect to the wastewater in the oil / fat decomposition tank.}
Item B5. Item 8. The treatment method according to any one of Items B1 to 4, wherein the dissolved oxygen concentration of the oil-containing wastewater in the oil-fat decomposition tank is 0.05 mg / L or more.
Item B6. Item 8. The treatment method according to any one of Items B1 to 5, wherein the pH of the oil-containing wastewater in the oil-fat decomposition tank is in the range of 4.5 to 9.0.
Item B7. Item 8. The treatment method according to any one of Items B1 to 6, wherein the temperature of the oil-containing wastewater in the oil-and-fat decomposition tank is in the range of 12 to 42 ° C.
Item B8. Item 8. The treatment method according to any one of Items B1 to 7, wherein the HRT of the oil / fat decomposition tank is 12 hours or more.
Item B9. Item 8. The treatment method according to any one of Items B1 to 8, wherein the C / N of the oil-containing wastewater in the oil-and-fat decomposition tank is in the range of 2 to 50.
Item B10. Item 8. The treatment method according to any one of Items B1 to 9, wherein the N / P of the oil-containing wastewater in the oil-and-fat decomposition tank is in the range of 1 to 20.

According to the method of the present invention, by continuously or intermittently adding a microbial preparation capable of decomposing fats and oils, the microbial preparations continuously flow in and out, effectively reducing the concentration of fats and oils in wastewater in which miscellaneous microorganisms are present. Can be made to. The present invention is characterized in that the microorganism does not necessarily have to grow in the fat / oil decomposition tank, and exhibits the effect of being able to decompose the fat / oil even if it cannot grow.

Further, in the present invention, there are miscellaneous microorganisms other than the input microorganisms, and the input microorganisms in which the wastewater containing fats and oils continuously flows in and out is a process in which the input microorganisms are difficult to grow. It is possible.

The method of the present invention is excellent in terms of cost because it can handle a wide range of fat and oil concentrations and can use a microbial preparation having a lower concentration than the conventional one.

In addition, or as an alternative, the method of the present invention can sufficiently decompose fats and oils in wastewater, and the amount of microorganisms input into the effluent from the decomposition tank is not larger than before, so that it can have an effect of being good for the environment.

It is a graph which shows the influence of the dissolved oxygen concentration (DO) on the decomposition of fats and oils by microorganisms. It is a graph which shows the influence of pH in the decomposition of fats and oils by microorganisms. It is a graph which shows the influence of temperature on the decomposition of fats and oils by microorganisms. It is a graph which shows the influence of C / N on the decomposition of fats and oils by microorganisms. It is a graph which shows the influence of N / P on the decomposition of fats and oils by microorganisms. It is a graph which shows the influence of the addition microorganism concentration at the time of addition by the intermittent type addition in the low-concentration fat (normal hexane value about 300 mg / L) wastewater. It is a graph which shows the influence of the addition microorganism concentration at the time of addition by the intermittent type addition in the wastewater of medium-concentration fats and oils (normal hexane value about 3000 mg / L). It is a graph which shows the influence of the addition microorganism concentration at the time of addition by the intermittent type addition in the wastewater of high-concentration fats and oils (normal hexane value about 10000 mg / L). It is a graph which shows the influence of the addition microorganism concentration at the time of addition by the intermittent type addition in the wastewater of ultra-high concentration fats and oils (normal hexane value about 30,000 mg / L). It is a graph which shows the influence of the addition microorganism concentration at the time of addition by the continuous type addition in the low-concentration fat (normal hexane value about 300 mg / L) wastewater. It is a graph which shows the influence of the addition microorganism concentration at the time of addition by the continuous addition in the wastewater of medium-concentration fat (normal hexane value about 3000 mg / L). It is a graph which shows the influence of the addition microorganism concentration at the time of addition by the continuous addition in the wastewater of high-concentration fat (normal hexane value about 10000 mg / L). It is a graph which shows the influence of the addition microorganism concentration at the time of addition by the continuous type addition in the wastewater of ultra-high concentration fats and oils (normal hexane value about 30,000 mg / L). It is a graph which shows the influence of the residence time in the wastewater of low-concentration fat (normal hexane value about 300 mg / L). It is a graph which shows the influence of the residence time in the wastewater of medium-concentration fat (normal hexane value about 3000 mg / L). It is a graph which shows the influence of the residence time in the wastewater of high-concentration fat (normal hexane value about 10000 mg / L). It is a graph which shows the influence of the residence time in the wastewater of ultra-high concentration fats and oils (normal hexane value about 30,000 mg / L). It is a figure which shows the system for the processing method of this invention.

Hereinafter, the present invention will be described in detail. Throughout the specification, it should be understood that the singular representation also includes its plural concept, unless otherwise stated. Therefore, it should be understood that singular articles (eg, "a", "an", "the", etc. in English) also include the plural concept unless otherwise noted. It should also be understood that the terms used herein are used in the meaning commonly used in the art unless otherwise noted. Thus, unless otherwise defined, all terminology and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, this specification (including definitions) takes precedence.

Hereinafter, definitions and / or basic technical contents of terms particularly used in the present specification will be described as appropriate.

As used herein, the term "comprise" also includes the meaning of "essentially consist of" and the meaning of "consist of".

Further, in the present specification, the normal hexane (n-Hex) value is the amount of non-volatile substances extracted by normal hexane, and is an index showing the amount of oil (fat, hydrolyzate, etc.) in water. .. The n-Hex value can be determined according to, for example, JIS K 0102. Alternatively, the n-Hex value of the present invention may be an equivalent value measured using, for example, a heat-sensitive polymer (for example, poly (N-isopropylacrylamide) (PNIPPAm)). The measurement of the PNIPPAm extract can be performed using, for example, a known kit such as the oil content measurement reagent set of Kyoritsu Institute of Physical and Chemical Research (Tokyo, Japan).

The oil-fat-containing wastewater treatment method of the present invention is a step of continuously or intermittently injecting a microbial preparation having an oil-fat decomposition ability into an oil-fat decomposition tank into which the oil-fat-containing wastewater continuously flows in and out to decompose the oil-and-fat. The input amount of the microbial preparation is an amount that allows the microorganisms to settle in the fat / oil decomposition tank, and the fat / oil-containing wastewater includes a step in which microorganisms other than the microorganisms contained in the microbial preparation are present.

The present invention is a technique for reducing the n-Hex value derived from fats and oils in wastewater and their hydrolyzate under appropriate process conditions.

The oil-and-fat-containing wastewater in the present invention is not particularly limited as long as it contains oil-and-fat, and is discharged from, for example, wastewater from restaurants, hospitals, hotels, etc., domestic wastewater, food processing factories, oil-and-fat processing factories, and the like. Industrial wastewater, etc.

The fats and oils in the wastewater in the present invention are not particularly limited, and for example, vegetable fats and oils (cottonseed oil, rapeseed oil, soybean oil, corn oil, olive oil, safflower oil, rice oil, sesame oil, palm oil, palm oil, peanut oil). Etc.), animal fats and oils (lard, beef tallow, milk fat, etc.), fish oil, processed products of these fats and oils (margarine, shortening, butter, etc.) and the like.

The n-Hex value of the oil-and-fat-containing wastewater in the present invention is not particularly limited, and is usually 100 to 40,000 mg / L, preferably 200 to 30,000 mg / L, and more preferably 300 to 30,000 mg / L. The present invention is particularly preferable for treating oil-containing wastewater having an average n-Hex value of more than 300 mg / L. In a preferred embodiment, in the method of the present invention, the n-Hex value of the oil-containing wastewater to be treated can be measured, and the amount of the microbial preparation to be added can be determined based on the measured value. The n-Hex value in the present invention may be specified according to JIS K 0102, or may be specified using an equivalent value measured using poly (N-isopropylacrylamide) (PNIPPAm)).

Microorganisms other than those contained in the microbial preparation are present in the oil-and-fat-containing wastewater in the present invention. Since the method of the present invention is usually carried out in an open system, it becomes an environment in which various microorganisms are present in the wastewater containing fats and oils. The number of microorganisms present in the oil-containing wastewater includes, for example, 1 × 10 ⁶ cells / mL or more, 1 × 10 ⁷ cells / mL or more, 1 × 10 ⁸ cells / mL or more, and 1 × 10 ⁹ cells / mL or more. Can be mentioned. Unlike pure culture, the environment in which such miscellaneous microorganisms are present is an environment in which it is difficult for the microorganisms of the introduced microbial preparation to grow.

In the present invention, the oil-and-fat-containing wastewater continuously flows into and out of the oil-and-fat decomposition tank. The term "continuous" as used herein does not mean only the case where the oil-containing wastewater is constantly flowing in and out, but also includes the case where the inflow and outflow are temporarily stopped. It should be noted that the term "continuous" in the present invention does not include systems such as batch processing in which microorganisms are introduced, proliferated, and decomposed in a closed tank.

The microbial preparation can be used without particular limitation as long as it has the ability to decompose fats and oils. As the microorganism in the microbial preparation, one kind alone or two or more kinds can be used together. When two or more species are mixed and used, it is desirable to use a combination of microorganisms capable of coexisting with each other. In addition, the microbial preparation may contain symbiotic bacteria that assist in the decomposition of fats and oils.

As an example of the microbial preparation, under the conditions of 22 to 35 ° C., pH = 5.5 to 8.5, DO ≧ 0.1 mg / L, and batch culture, n-Hex value = 10000 mg / L equivalent fats and oils and hydrolysis. Examples thereof include a microbial preparation capable of decomposing the fatty acid of the decomposition product product within 72 hours, preferably within 48 hours, more preferably within 36 hours, and even more preferably within 24 hours by 80% or more.

As the microbial preparation, a microorganism that produces lipase and a microorganism that decomposes fatty acids (which are decomposition products of fats and oils by lipase) and / or glycerol can be preferably used. As such a microorganism, not only a microorganism having these properties alone, but also a microorganism having a plurality of these properties (for example, a microorganism that produces lipase and decomposes fatty acids) can be used.

Examples of microorganisms that produce lipase include eubacteria, yeasts, filamentous fungi and the like, preferably eubacteria and yeasts, and more preferably eubacteria. Examples of eubacteria include Bacillus bacterium, Corynebacterium bacterium, Rhodococcus bacterium, Burkholderia bacterium, Acinetobacter bacterium, and Acinetobacter bacterium. Bacteria of the genus, Alcaligenes, Bacteria of Rhodobacter, Bacteria of Ralstonia, Bacteria of Acidovorax, Bacteria of Serratia, Bacteria of Flavobacterium, etc. Can be used. Among them, Burkholderia bacteria, particularly Burkholderia arboris (for example, SL1B1 strain (NITE P-724)) are preferable.

Examples of microorganisms that decompose (assimilate) glycerol include eubacteria, yeasts, filamentous fungi and the like, preferably eubacteria and yeasts, and more preferably yeasts. As the yeast, Candida genus yeast, particularly Candida silindracea (for example, SL1B2 strain (NITE P-714), etc.) is preferable.

Examples of microorganisms that decompose (assimilate) fatty acids include eubacteria, yeasts, filamentous fungi and the like, preferably eubacteria and yeasts, and more preferably yeasts. Yeasts include Yarrowia yeast, Cryptococcus yeast, Trichosporon yeast, and Hansenula yeast, especially Yarrowia lipolytica (eg, 1A1 strain (NITE BP-167)). Is preferable.

Specific examples of the microorganisms used in producing the microbial preparation include Burkholderia alboris, Candida silindracea, and Yarrowia lipotica, and it is desirable to use two or three of these in combination.

Microorganisms can be produced by culturing by a known method. Examples of the form of the microbial preparation include a liquid state, a dry state, a paste state, and a state of being adsorbed on powder / granules such as sawdust. In addition, the microbial preparation can also be used in a state of being fixed on a carrier.

Washout can be avoided by using such a carrier. The material of the carrier is not particularly limited as long as it can fix microorganisms. For example, carbon fiber (PAN-based, pitch-based, phenol resin-based, etc.), polyethylene resin, polypropylene resin, polyurethane resin, polystyrene resin, poly Examples thereof include vinyl chloride resin, polyvinyl acetate resin, polyvinyl alcohol resin, polyethylene glycol resin, acrylic resin, gelatin, sodium alginate, carrageenan, dextrin, ceramics, silicon, metal, and composites thereof. It is preferable to use a porous or fibrous carrier in order to increase the immobilization rate of microorganisms and the efficiency of action of microorganisms. Further, the gel-like carrier may contain microorganisms. Examples of the shape of the carrier include a cube, a rectangular parallelepiped, a columnar shape, a spherical shape, a disk shape, a sheet shape, and a film shape. However, in the method of the present invention, since a sufficient oil / fat decomposition effect can be obtained without using such a carrier, the use of a carrier is not essential.

The method of charging the microbial preparation into the fat decomposition tank is either a continuous type or an intermittent type. The intermittent method means a method in which a microbial preparation is regularly added.

The amount of the microbial preparation charged into the fat decomposition tank is an amount that allows the microorganisms to (stablely) settle in the fat decomposition tank. Here, "fixation" means a state in which the target microorganism is present in the fat / oil decomposition tank to the extent that the fat / oil can be decomposed without being selected. That is, even under the condition that the wastewater continuously flows out, the introduced microorganisms are not washed out.

In a preferred embodiment, no carrier is used in the fat decomposition method of the present invention. Unexpectedly, the present invention determines the amount of microbial input according to the fat content of the treated wastewater without using a carrier, and the microbial concentration in the fat decomposition tank is lower than before, so that the wastewater is being drained while avoiding washout. It has made it possible to sufficiently decompose the fats and oils of. Washout is a phenomenon in which the outflow rate of a continuous system cannot be adjusted to the cell growth rate and the concentration cannot be maintained. In general, an ideal continuous system is in a steady state, and the following equation holds.
Input microbial amount (cell / h) + microbial growth amount (cell / h) = outflow microbial amount (cell / h)
here,
Amount of microbial preparation (cell / h) = microbial preparation microbial concentration (cell / L) x microbial preparation addition rate (L / h)
Microbial growth rate (cell / h) = specific growth rate (1 / h) x microbial concentration in the tank (cell / L) x tank capacity (L)
Outflow microbial amount (cell / h) = effluent microbial concentration (cell / L) x effluent outflow rate (L / h)
Is.

Usually, the amount of input microorganisms is orders of magnitude lower than the amount of microorganisms grown in the tank, and it was generally recognized in the field to try wastewater treatment with the grown microorganisms. However, the present inventor does not intend to grow the microorganisms, and examines whether the introduced microorganisms can be supplemented even if they do not grow.
We considered supplementing with the amount of input microorganisms = the amount of outflow microorganisms. The following formula holds when the introduced microorganism does not grow.
Microbial concentration in microbial preparation x amount of microbial preparation added = microbial concentration in effluent x volume of fat decomposition tank, that is,
Microbial concentration in microbial preparation x amount of microbial preparation added / volume of oil / fat decomposition tank = concentration of microbial agent added at the time of injection = concentration of microorganism in effluent That is, the concentration of microbial agent added is responsible for the decomposition of oil / fat in wastewater. In this field, it has been recognized that in order to sufficiently decompose fats and oils, it is necessary to proliferate microorganisms and achieve fats and oils decomposition by the grown microorganisms, but the present inventor unexpectedly depends on the concentration of input microorganisms. It was found that fat decomposition can be achieved without depending on the growth of microorganisms. Of course, even when the introduced microorganism grows, the advantages of the present invention can be enjoyed as well.

Normally, a microorganism consumes a carbon source, and the amount obtained by multiplying the consumption amount by the cell yield is converted into a cell component and proliferated. Since the carbon source in the decomposition of fats and oils is fats and oils, in theory, bacterial cells grow as the fats and oils are decomposed. The amount of growth is determined by the bacterial cell yield, which is about 0.5 in most cases, but varies depending on the environmental conditions. That is, in terms of carbon balance, half of the decomposed fats and oils are usually grown cells, and the other half is mineralized to carbon dioxide while being used as an energy source for maintaining the cells of the cells. Non-proliferation basically means that the apparent yield of cells is zero, and all of the decomposed fats and oils are used to maintain the cells, or the grown cells die at the same rate. It means that it is or has been weeded out. This is an unusual event and is not a common operation taught by biochemical engineering, which is the basis of wastewater treatment theory. However, the inventor has found that such an operation is possible by balancing the amount of fats and oils and the amount of input microorganisms when the competition for survival with other microorganisms is fierce. If this balance is lost and the amount of microorganisms input is too small with respect to the amount of fats and oils, there is room for microorganisms to grow, but excess fats and oils remain. On the contrary, when the amount of input microorganisms is too large with respect to the amount of fats and oils, the carbon source required for maintaining the cells cannot be obtained, and the concentration of microorganisms decreases. Such a condition causes a state in which input microorganisms are wasted. That is, one of the most important aspects of the present invention is to find the amount of input cells according to the amount of fats and oils in the wastewater in which miscellaneous microorganisms are present and the competition for survival is fierce.

When the microbial preparation is intermittently charged into the oil / fat decomposition tank, the amount of the microbial preparation to be added is preferably 5.0 × 10 ^{4 to} 1.0 × 10 ⁷ cells / mL with respect to the wastewater in the oil / fat decomposition tank. It is preferably 1.0 × 10 ^{5 to} 1.0 × 10 ⁷ cells / mL, more preferably 5.0 × 10 ^{5 to} 5.0 × 10 ⁶ cells / mL, and most preferably 1.0 × 10 ^{6 to} 3. The amount is 0.0 × 10 ⁶ cells / mL. It is desirable to set the charging interval of the microorganisms that are regularly charged within 24 hours from the residence time of the wastewater in the fat decomposition tank. The input amount of the microbial preparation here can also be the concentration of the type of microorganism contained most in the microbial preparation.

When the microbial preparation is continuously added, FX, F, and IX are substituted into the following formula to obtain SX.

Microbial product supply rate (FX): Treated wastewater flow rate (F)
= Microbial concentration (IX) after influx dilution in oil and fat decomposition tank: Supply microbial concentration (SX)
IX, compared drainage fat splitting bath, preferably ^{5.0 × 10 4 ~1.0 × 10 7} cells / mL, more preferably ^{1.0 × 10 5 ~1.0 × 10 7} cells / mL , More preferably 5.0 × 10 ^{5 to 5.0 × 10 6} cells / mL, and most preferably 1.0 × 10 ^{6 to} 3.0 × 10 ⁶ cells / mL. Further, FX: F is typically 1: 1000, but is not limited to this. The concentration of the supplied microorganisms here can also be the concentration of the type of microorganism contained most in the microbial preparation.

When a plurality of types of microorganisms are used, each microorganism can be charged into the oil / fat decomposition tank at the same time or separately.

The dissolved oxygen concentration (DO) of the oil-containing wastewater in the oil-fat decomposition tank is usually 0.05 mg / L or more, preferably 0.1 mg / L or more, more preferably 0.5 mg / L or more by aeration stirring or the like. Most preferably, it is preferably maintained at 1 mg / L or more.

The pH of the oil-containing wastewater in the oil-fat decomposition tank is usually in the range of 4.5 to 9.0, preferably 5.5 to 8.5, and more preferably 6.0 to 8.0. If it does not fall within these ranges, the pH can be adjusted as appropriate by adding an acid or alkali.

The temperature of the oil-containing wastewater in the oil-and-fat decomposition tank is usually 12 ° C. to 42 ° C., preferably 15 ° C. to 40 ° C., more preferably 15 to 37 ° C., still more preferably 18 to 37 ° C., and most preferably 20 to 35 ° C. It is desirable to keep it within the range of. If the temperature does not fall within these temperature ranges, the temperature can be appropriately adjusted by heating or cooling.

In a typical embodiment, the present invention targets oil and fat decomposition such that the HRT (hydraulic residence time) of the oil and fat decomposition tank is 1 hour or more. Specifically, the HRT of the oil / fat decomposition tank is usually 12 hours or more, preferably 18 hours or more, more preferably 20 hours or more, still more preferably 24 hours or more. When a reduction of 80% or more in the n-Hex value is expected for wastewater having an n-Hex of more than 10000 mg / L, the HRT is usually set to 18 hours or longer, preferably 20 hours or longer, more preferably 24 hours or longer. .. For wastewater with an n-Hex value of 3000 mg / L or less, if an 80% or more reduction in the n-Hex value is expected, the HRT is usually 8 hours or longer, preferably 12 hours or longer, more preferably 18 hours or longer. To do. Typically, for any treatment, HRT can be within 48 hours.

In the wastewater flowing into the fat decomposition tank, nitrogen is available in a form available to microorganisms, preferably ammonium salts, nitrates, sulfates, or organic nitrogen compounds, more preferably ammonium sulfates, ureas, amino acids, or peptones, triptons, casaminos. It is desirable that it exists in a form containing a peptide such as an acid. The amount of nitrogen required is preferably estimated in advance from lab-scale or pilot-scale tests, generally in the range C / N = 2-50 (where C refers to carbon derived only from n-Hex). C / N = 2 to 30, more preferably C / N = 2 to 20. However, C / N is the weight ratio of n-Hex-derived carbon atoms and nitrogen atoms contained in the wastewater. If the nitrogen in the wastewater is insufficient and does not fall within the above range, a required amount of nitrogen may be added in the form described above, preferably in the form of ammonium sulfate or urea. In another embodiment, nitrogen can be added by supplying as ammonia or an aqueous solution thereof in accordance with the automatic adjustment of pH, which also serves to control the decrease in pH due to the decomposition of fats and oils. This supply may be automatic or manual.

It is desirable that phosphorus (P) is present in the wastewater flowing into the fat decomposition tank in a form that can be used by microorganisms, preferably in the form of phosphate or nucleic acid, and more preferably in the form of phosphate. The amount of phosphorus required should be estimated from lab-scale or pilot-scale tests and is generally such that N / P = 1-20 with respect to nitrogen in wastewater. However, N / P is a weight ratio of nitrogen atoms and phosphorus atoms contained in wastewater. If the amount of phosphorus in the wastewater is insufficient and does not fall within the above range, a required amount of phosphorus can be added in the form of a phosphate. This addition may be automatic or manual.

The microbial concentration in the fat decomposition tank depends on the fat concentration in the wastewater, and the higher the fat concentration, the higher the bacterial cell concentration is maintained. If the concentration of the input microorganisms is low, the growth becomes active due to the fats and oils in the wastewater, so that the concentration of microorganisms may be rather high. On the contrary, if the amount of input microorganisms is sufficient, the fat and oil concentration may be sufficiently lowered, and the amount of microorganisms may be maintained at a low concentration.

When the oil / fat decomposition tank foams, as a countermeasure, defoaming operations such as shortening the HRT, showering, and adding a defoaming agent can be performed. However, since some antifoaming agents inhibit the growth of microorganisms, it is desirable to set the amount to be added in consideration of the relevant matters.

If the wastewater contains chlorine, antibiotics, etc. that suppress the growth of microorganisms, the latter stage (for example, adjustment) after the removal treatment or the concentration of these growth-suppressing substances is reduced in consideration of the entire wastewater treatment system. Microbial preparations can be added to (after the tank).

The n-Hex value of the effluent from the oil / fat decomposition tank is preferably 60 mg / L or less, more preferably 30 mg / L in the case of low-concentration wastewater in which the n-Hex value of the inflow water is about 300 mg / L or less. It is as follows. In the case of medium-concentration wastewater having an n-Hex value of about 3000 mg / L, the inflow water is preferably 600 mg / L or less, more preferably 300 mg / L or less, still more preferably 150 mg / L or less, and most preferably 30. It is mg / L or less. In the case of high-concentration wastewater having an n-Hex value of about 10000 mg / L, the inflow water is preferably 1000 mg / L or less, more preferably 500 mg / L or less, still more preferably 100 mg / L or less, and most preferably 30. It is mg / L or less. In the case of high-concentration wastewater having an n-Hex value of about 30,000 mg / L or more, the inflow water is preferably 3000 mg / L or less, more preferably 1000 mg / L or less, and further preferably 300 mg / L or less.

Further, according to the method of the present invention, the n-Hex value of the oil-and-fat-containing wastewater can be reduced by preferably 80% or more, more preferably 90% or more, further preferably 95% or more, and most preferably 99% or more.

As a result, in many wastewaters, it is possible to reduce the n-Hex value of the effluent from the oil / fat decomposition tank to less than 30 mg / L, which is the standard value for discharge to the sewer in many local governments. When this reference value is achieved, if only the n-Hex value is focused on, even the main treatment such as the activated sludge treatment in the subsequent stage becomes unnecessary.

It has been conventionally recognized in the art that microorganisms need to be sufficiently grown in order to decompose fats and oils by microorganisms in a continuous system, but the present inventor unexpectedly recognized that as much as the conventional recognition. It was discovered that fat decomposition can be achieved without the growth of microorganisms. Until now, it was considered necessary to grow microorganisms in an amount of several hundred times or more and several thousand times or less with respect to the amount of input microorganisms, but the present inventor has made it 100 times or less with respect to the amount of input microorganisms, or It has been found that wastewater treatment can be carried out successfully even if the microorganisms are grown only up to several tens of times the amount. For example, the amount of microorganisms added to the effluent is preferably 0.01 times or more and 100 times or less, 0.01 times or more and 10 times or less, 0.1 times or more and 100 times or less, 0.1 times the amount added. Double or more and 10 times or less, 0.5 times or more and 100 times or less, 0.5 times or more and 10 times or less, 1 time or more and 100 times or less, 1 time or more and 10 times or less, preferably 0.1 times or more and 10 times or less. Is. Therefore, in one embodiment, the amount of introduced microorganisms in the effluent from oil decomposition vessel may be less 1 × 10 ⁸ cells / mL. As a result, the amount of microorganisms in the effluent was suppressed, and the impact on the environment could be reduced. Since the amount of growth of microorganisms depends on the amount of fats and oils that are the food (carbon source), the amount of microorganisms to be added is controlled according to the amount of fats and oils in the wastewater, and efficient fat and oil decomposition is achieved. it can. In the past, there was no information on the amount of microorganisms required for the amount of fats and oils that had to be treated. ^{In one embodiment, the amount of the microbial preparation charged into the fat decomposition tank is 3.0 × 10 4 to} 1.0 × 10 ⁸ per 1 mg of the normal hexane extract in the oil-containing wastewater flowing into the fat decomposition tank. The cells, preferably 3.0 × 10 ⁴ to 1 × 10 ⁷ cells. By determining the amount of the microbial preparation to be added according to the amount of the normal hexane extract in the oil-containing wastewater flowing into the oil-and-fat decomposition tank in this way, efficient oil-and-fat decomposition is achieved without consuming unnecessary microorganisms. Can be done.

The oil-and-fat-containing wastewater treatment method of the present invention can include additional steps in addition to the above steps. Examples of such a step include a step of returning all or a part of the effluent from the oil / fat decomposition tank to the oil / fat decomposition tank again. However, in the method of the present invention, a sufficient oil / fat decomposition effect can be obtained without performing such a return treatment, so it is essential to return all or part of the effluent from the oil / fat decomposition tank to the oil / fat decomposition tank again. is not it.

Usually, in a batch culture of pure microorganisms, the microorganisms grow by orders of magnitude while consuming the carbon source of the substrate. It typically grows hundreds of times. This was common sense in biotechnology. However, in the flow of wastewater in which innumerable types and numbers of microorganisms are present, even if fats and oils that serve as nutrients for input microorganisms are present, it is difficult to increase the number by several hundred times as in batch culture of pure microorganisms. Under conditions where the concentration of fats and oils is not very high, the concentration of microorganisms may even decrease.

However, even under such conditions, according to the present invention, efficient decomposition of fats and oils is possible. The present invention is not based on how to grow the input microorganisms in the wastewater, but based on a new concept that the input microorganisms having a certain concentration or more corresponding to the concentration of fats and oils should be present in the wastewater.

According to the method of the present invention, by continuously or intermittently putting a microbial preparation having an oil / fat decomposition ability into an oil / fat decomposition tank, it continuously flows in and out, and even if it is wastewater in which miscellaneous microorganisms are present, the oil / fat It is possible to effectively reduce the concentration of. In the present invention, the microorganism does not necessarily have to grow in the fat decomposition tank, and can decompose fats and oils even if it cannot grow.

Further, in the present invention, there are miscellaneous microorganisms other than the input microorganisms, and the input microorganisms are difficult to grow because the wastewater containing oil and fat continuously flows in and out. However, the microorganisms are not washed out and the oil and fat decomposition tank. It can be fixed inside.

The method of the present invention is excellent in terms of cost because it can handle a wide range of fat and oil concentrations and is effective with a lower amount of microorganisms than before.

(Devices and systems)
The present invention may also provide an apparatus or system for use in the processing methods of the present invention. The apparatus or system of the present invention may typically include a storage tank for the microbial preparation, an amplification tank for the microbial preparation, and a fat decomposition tank into which the oil-containing wastewater continuously flows in and out (FIG. 18).

The storage tank for the microbial preparation in the apparatus or system of the present invention is a tank for storing the microbial preparation as a seeding source and has a capacity of 30 to 200 L, but the capacity is not limited thereto. The storage tank of the present invention is typically made of metal, plastic or glass, but is not limited thereto. The storage tank of the present invention may be provided with a blower for aeration, if necessary. In FIG. 18, the storage tank is stored in the refrigerator, but is not necessarily limited to this.

In a preferred embodiment, a plurality of types of microorganisms are used as inoculum in the method of the present invention, and the storage tank of the present invention can be provided with a plurality of storage tanks for individually storing various types of microorganisms. By storing each type of microorganism individually in this way, the activity of the microorganism in the microbial preparation can be maintained for a long period of time.

The microbial amplification tank of the present invention can typically be a cylindrical or square tubular, metal, plastic or glass tank with a volume of 30-1000 L. Preferably, the amplification tank is equipped with a thermometer and a thermometer, and can control the temperature during microbial culture (amplification). The controlled temperature is typically 18-35 ° C, preferably 25-33 ° C, more preferably 28-30 ° C. A water level gauge or a liquid level sensor L1 may be installed in the amplification tank to enable control of the lower limit, upper limit, and middle level of the liquid level. Further, this liquid level sensor may also serve as a foaming sensor, or a system for detecting firing may be installed based on another principle. A system that automatically supplies an antifoaming agent in conjunction with a system that senses foaming may be provided. Also, the amplification tank may be equipped with a blower.

The amplification tank of the present invention can be automatically supplied with the microbial preparation stored in the storage tank by the pump P1, the nutritional supplement by the pump P2, and the activator by the pump P3 in a specified amount.

The activator is stored in an activator tank, which stores a solution of inorganic salts containing nutrients necessary for microbial growth, typically 3-100 L, preferably 3-100 L. A 10-50 L tank, typically made of metal, plastic or glass, preferably plastic. The activator tank can be stored in the refrigerator.

Nutrients are stored in nutrient tanks, which store oils that are the carbon source for microorganisms, typically in tanks with a capacity of 3-100 L, preferably 10-50 L, typically. It is made of metal, plastic or glass, preferably plastic. The nutrient tank can be stored in the refrigerator.

Although not shown, the system of the present invention further stores a tank of typically 3-100 L, preferably 10-50 L, for storing organic matter other than oil, which is a carbon source for microorganisms, or a solution thereof. May be provided, the tank is typically made of metal or plastic or glass, preferably plastic. This tank can be stored in the refrigerator.

The culture tank and the preparation tank may be equipped with a diffuser tube or a balloon, or a microbubble / nanobubble generator.

The microorganisms grown in the microbial culture tank are put into the oil / fat decomposition tank of the present invention via the pump P4, and the oil / fat decomposition in the wastewater is performed in the oil / fat decomposition tank. The oil / fat decomposition tank of the present invention may include a tank, a blower, and a sensor L2. The sensor L2 of the fat decomposition tank can detect one or more of temperature, pH, dissolved oxygen concentration, and foaming level.

In one embodiment, the apparatus or system of the present invention also controls a computer program (also simply referred to as a "program") that implements the oil-containing wastewater treatment method of the present invention, and / or the apparatus or system of the present invention. It may be provided with an execution / control unit that stores a program for the operation. The present invention also contains a recording medium (eg, CD-R, DVD, USB) containing a program for implementing the oil-containing wastewater treatment method of the present invention and / or a program for controlling the apparatus or system of the present invention. Flash) provide memory, etc.).

In such a program, for example, the apparatus of the present invention comprises a step of continuously or intermittently injecting a microbial preparation having an oil / fat decomposition ability into an oil / fat decomposition tank in which oil / fat-containing wastewater continuously flows in / out to decompose the oil / fat. Alternatively, it may be coded to be performed by a system or to implement control of the device or system. The implementation / control unit or program used in the present invention is configured to calculate and / or control the input amount of the microbial preparation used so as to be an amount that allows the microorganism to settle in the fat decomposition tank. This implementation / control unit or program sets the input amount of the microbial preparation to 5.0 × 10 ^{4 to} 1.0 × 10 ⁷ cells / mL with respect to the wastewater in the oil / fat decomposition tank, or the oil / fat. ^{For example, 3.0 × 10 4 to} 1.0 × 10 ⁸ cells, preferably 3.0 × 10 ^{4 to} 1.0 × 10 ⁷ cells, per 1 mg of the normal hexane extract in the oil-containing wastewater flowing into the decomposition tank. It may be configured to implement controlling the device or system of the present invention. This input amount may be appropriately changed according to the actual implementation situation based on the description in the present specification. The apparatus or system of the present invention may also be configured to be able to measure the amount of wastewater and the values for the normal hexane extract in the wastewater to determine the input amount.

Various functions realized by the implementation / control unit or the program of the present invention may be partially or wholly realized manually.

Various functions realized by the implementation / control unit or the program of the present invention may be realized or optimized in part or in whole by artificial intelligence (AI) or machine learning.

In one embodiment, the apparatus or system of the present invention may also be configured to be able to control the dissolved oxygen concentration of the oil-containing wastewater in the oil-fat decomposition tank. Such a configuration may be provided separately with an oxygen concentration control unit for controlling the oxygen concentration, may be realized by the above-mentioned implementation / control unit or control by a program, and a part or all thereof may be realized manually. In some cases, some or all of them may be realized or optimized by artificial intelligence (AI) or machine learning. The oxygen concentration is supplied by an air supply source such as a blower or a compressor, and the supply amount is automatically adjusted in conjunction with the dissolved oxygen concentration. Further, in order to increase the dissolution efficiency of oxygen, a stirring device or the like may be provided to control the stirring speed so as to be linked with the dissolved oxygen concentration. Furthermore, a system is incorporated that indirectly monitors the decomposition activity based on the fluctuation of dissolved oxygen, determines that oil decomposition has been completed or has not progressed when there is almost no decrease in dissolved oxygen, and controls the input microbial preparation amount by feedback. It may be.

In one embodiment, the apparatus or system of the present invention may also be configured to control the pH of the oil-containing wastewater in the oil-decomposing tank. Such a configuration may be provided separately with a pH control unit for controlling the pH, may be realized by the above-mentioned implementation / control unit or control by a program, or a part or all thereof may be realized manually. , Part or all of which may be realized or optimized by artificial intelligence (AI) or machine learning. The pH can be controlled by any means or method known in the art, for example by adding an appropriate amount of acid or alkali. Therefore, for pH control, the pH is measured, the amount of acid and / or alkali to be charged is calculated based on the measured value and other parameters (eg volume, etc.) and based on the calculation result. This can be achieved by adding acid and / or alkali. In a preferred embodiment, as shown in FIG. 18, the oil / fat decomposition tank may include a pH adjusting tank that automatically adjusts the pH when the pH falls outside the set range. In one embodiment, the pH adjustment tank automatically adds 2N sulfuric acid or 2N sodium hydroxide aqueous solution to the fat decomposition tank via a pump P6, for example, when the pH is out of the set range, and decomposes the fat. The pH in the tank can be adjusted within the set range. Alternatively, instead of sodium hydroxide, ammonia or an aqueous solution thereof may be added also as a supply of a nitrogen source. Furthermore, by utilizing the fact that the treated water in the tank becomes acidic as the decomposition of fats and oils progresses, the decomposition activity is indirectly monitored based on the decrease in pH or the consumption of alkali, and the amount of the input microbial preparation is feedback-controlled. The system may be incorporated.

In one embodiment, the apparatus or system of the present invention may also be configured to control the temperature of the oil-containing wastewater in the oil-decomposing tank. Such a configuration may be realized by separately providing a temperature control unit, temperature control may be realized by the above-mentioned implementation / control unit or control by a program, and a part or all thereof may be realized manually. It may be realized or optimized in part or in whole by artificial intelligence (AI) or machine learning. Such temperature control preferably includes, but is not limited to, the ability to control within the range of 12-42 ° C. Temperature control can be achieved by any means known in the art. In a preferred embodiment, as shown in FIG. 18, when the temperature measured by the sensor L2 falls below the set range, the drainage is heated by the heater and the temperature can be raised to the set range. Alternatively, waste heat such as boiler waste heat, direct addition of high-temperature wastewater, and heat exchange can be used. Further, when the temperature measured by the sensor L2 exceeds the set temperature range, the drainage is cooled by the cooler, and the temperature can be lowered to the set temperature. Alternatively, injection of cooling water, heat exchange with cold water, and supply of cold air can be used. Furthermore, by utilizing the principle that the temperature rises due to the heat of fermentation due to decomposition, a system that senses the degree of temperature rise or the operation of the cooling system and feedback-controls the amount of the input microbial preparation may be incorporated.

In one embodiment, the apparatus or system of the present invention may also be configured to control the C / N of the oil-containing wastewater in the oil-decomposing tank. The range of C / N of this oil-containing wastewater is preferably 2 to 50, 2 to 30, or 2 to 20, but is not limited to this. Such C / N control may be realized by separately providing a C / N control unit, or C / N control may be realized by the control by the implementation / control unit or the program, and a part thereof. Alternatively, all may be realized manually, and some or all of them may be realized or optimized by artificial intelligence (AI) or machine learning. If the nitrogen in the wastewater is insufficient and does not fall within the above range, a required amount of nitrogen (preferably ammonium sulfate or urea) can be added from the N source tank via, for example, pump P7 (FIG. 18). Alternatively, aqueous ammonia or the like can be added in a form linked with pH adjustment.

In one embodiment, the apparatus or system of the present invention may also be configured to control the N / P of the oil-containing wastewater in the oil-decomposing tank. The range of N / P of this oil-containing wastewater is preferably 1 to 20, 1 to 10, or 1 to 5, but is not limited to this. Such N / P control may be realized by separately providing an N / P control unit, or N / P control may be realized by the above-mentioned implementation / control unit or control by a program, and a part thereof. Alternatively, all may be realized manually, and some or all of them may be realized or optimized by artificial intelligence (AI) or machine learning. If the above range is not met due to lack of phosphorus in the effluent, the required amount of phosphorus can be added in the form of phosphate from the P source tank, for example via pump P8 (FIG. 18). Further, the aqueous solution containing the above-mentioned nitrogen source and phosphate can be stored in one tank as one activator prepared in advance so that the N / P is in the above-mentioned range, and can be supplied together.

In one embodiment, the apparatus or system of the present invention may also be configured to control the amount of microorganisms input into the effluent from the fat decomposition tank. Such control of the amount of input microorganisms may be realized by separately providing an input microorganism amount control unit, or control by the above-mentioned implementation / control unit or program may realize control of the amount of input microorganisms, and a part thereof. Alternatively, all may be realized manually, and some or all of them may be realized or optimized by artificial intelligence (AI) or machine learning.

In a preferred embodiment, the fat decomposition tank may also include a foaming sensor for detecting foaming conditions. The oil / fat decomposition tank may further include a defoaming tank that automatically charges a defoaming agent when foaming is detected by a foaming sensor. Furthermore, since it often indicates that the decomposition of fats and oils is active during foaming, a system that uses this to feed back control the amount of microbial preparation input in conjunction with the addition of a foaming sensor or antifoaming agent. May be incorporated.

The oil / fat decomposition tank of the present invention may be further equipped with a water sampling pump that samples a required amount at a specified date and time, and the liquid can be sent to a water sampling tank in the refrigerator according to the setting.

In one embodiment, the oil / fat decomposition tank of the present invention may be provided with a confirmation means for confirming the degree of oil / fat decomposition of wastewater in the oil / fat decomposition tank. The confirmation by this confirmation means may be, for example, centrifuging the wastewater and evaluating the degree of oil / fat decomposition from the state of the supernatant.

The wastewater treated in the oil / fat decomposition tank can be subjected to a subsequent treatment of an activated sludge tank or the like via, for example, a pump P9.

Hereinafter, examples will be given to explain the present invention in more detail. However, the present invention is not limited to these examples and the like.

Test Example 1: Effect of Dissolved Oxygen Concentration (DO) 7 L of food factory wastewater containing oil with an n-Hex value of about 10,000 mg / L was charged into a 10 L fermenter (manufactured by Biot Co., Ltd.), and various dissolved oxygen concentrations Below, a decomposition test was carried out at 30 ° C. with a batch of oil content. Incidentally, during this wastewater, originally the microorganisms of about 3 × 10 ⁸ cells / mL are present, it was shown from the colony counts on LB agar medium. The microbial preparations using a mixed formulation of Burkholderia arboris and Yarrowia lipolytica, as the concentration of microorganisms the former is 1.0 × 10 ⁶ cells / mL, were inoculated at the beginning degradation test. Since the latter microbial concentration is usually about 1/10 of the number of cells during inoculation and culturing, the former concentration is taken as the total input microbial concentration.

The dissolved oxygen concentration (DO) was constantly monitored by a galvanic fermentation DO electrode and adjusted by the amount of aeration and the stirring speed. During the decomposition test, the pH was constantly monitored by a closed pH electrode and automatically adjusted to 6.0 to 8.0 by adding dilute hydrochloric acid and an aqueous sodium hydroxide solution. The test solution was sampled over time, and the concentration of the n-Hex extract was measured according to JIS K 0102. The batch test was performed 3 times and the standard error was shown in the graph. The results are shown in FIG.

Test Example 2: Effect of pH The same 7L of food factory wastewater as in Test Example 1 was charged into a 10L fermenter (manufactured by Biot Co., Ltd.), and a decomposition test of oil was carried out at 30 ° C. by batch under various pH conditions. .. The same microbial preparation as in Test Example 1 was used, and the cells were inoculated at the start of the decomposition test so that ^{the concentration of Burkholderia arboris was 1.0 × 10 6 cells / mL.} During the decomposition test, aeration stirring was performed so that the DO was 1.0 or more. The measurement and adjustment of DO and pH were also carried out in the same manner as in Test Example 1. The test solution was sampled over time, and the concentration of the n-Hex extract was measured by the same method as in Test Example 1. The batch test was performed 3 times and the standard error was shown in the graph. The results are shown in FIG.

Test Example 3: Effect of temperature 7 L of food factory wastewater, the same as in Test Example 1, was charged into a 10 L fermenter (manufactured by Biot Co., Ltd.), and a decomposition test of oil was carried out by batch under various temperature conditions. The same microbial preparation as in Test Example 1 was used, and the cells were inoculated at the start of the decomposition test so that ^{the concentration of Burkholderia arboris was 1.0 × 10 6 cells / mL.} During the decomposition test, aeration was stirred so that the DO was 1.0 or more, and the pH was adjusted to 6.0 to 8.0. The measurement and adjustment of DO and pH were also carried out in the same manner as in Test Example 1. The test solution was sampled over time, and the concentration of the n-Hex extract was measured by the same method as in Test Example 1. The batch test was performed 3 times and the standard error was shown in the graph. The results are shown in FIG.

Test Example 4: Effect of carbon to nitrogen ratio (C / N) 10 L fermenter (manufactured by Biot Co., Ltd.) containing 7 L of inorganic salt medium containing 1% of canola oil (equivalent to about 10,000 mg / L of n-hex). The decomposition test of the oil content was carried out by batch at 30 ° C. and pH 6.0 to 8.0 under various C / N (weight ratio of each element) conditions. The composition of the mineral salts medium _{is, Na 2 HPO 4 3.5g / L} , KH 2 PO 4 2.0g / L, (NH 4) 2 SO 4 0.775~3.6g / L, MgCl 2 · 6H 2 O _{0.34g / L, FeSO 4 · 7H} 2 O 2.8mg / L, MnSO 4 · 5H 2 O 2.4mg / L, CoCl 2 · 6H 2 O 2.4mg / L, CaCl 2 · 2H 2 O 1. _{7mg / L, CuCl 2 · 2H} 2 O 0.2mg / L, ZnSO 4 · 7H 2 O 0.3mg / L, was NaMoO 4 0.25mg / L. C / N was adjusted for 10 or more by changing the concentration of ammonium sulfate ((NH ₄ ) ₂ SO _4). When C / N was 2 or less, urea was added to this to adjust.

The carbon content of canola oil was calculated in terms of trioleic acid. To this, 1 L of activated sludge from a sewage treatment plant known to have an n-Hex value of 100 mg / L or less was centrifuged, and resuspended in 50 mL of the above-mentioned inorganic salt medium was added. As a result, a test solution was prepared in which culturable microorganisms of about ^{5 × 10 6 cells / mL were pre-existing.} Thereto, the same microorganism formulation as in Test Example 1, so that the concentration of Burkholderia arboris is 1.0 × ¹⁰ 6 cells / mL, were inoculated at the beginning degradation test. During the decomposition test, aeration stirring was performed so that the DO was 1.0 or more. The measurement and adjustment of DO and pH were also carried out in the same manner as in Test Example 1. The test solution was sampled over time, and the concentration of the n-Hex extract was measured according to JIS K 0102. The batch test was performed 3 times and the standard error was shown in the graph. The results are shown in FIG.

Test Example 5: Effect of nitrogen to phosphorus ratio (N / P) 7 L of inorganic salt medium containing 1% of canola oil (equivalent to about 10,000 mg / L of n-Hex) was charged into a 10 L fermenter (manufactured by Biot Co., Ltd.). , Under various N / P (weight ratio of each element) conditions, a decomposition test of oil was carried out by batch at 30 ° C. and pH 6.0-8.0. The composition of the inorganic salt medium is the same as that of Test Example 4 except for the concentrations of ammonium sulfate and phosphate. The concentration of the nitrogen source (NH ₄ ) ₂ SO ₄ was fixed at 4 g / L, and the concentration of N / P was adjusted by changing the concentrations of the _{phosphorus sources Na 2} HPO ₄ and KH ₂ PO _4. However, Na ₂ HPO ₄ : KH ₂ PO ₄ (weight ratio) was fixed at 3.5: 2.

The same microbial preparation as in Test Example 1 was used, and the cells were inoculated at the start of the decomposition test so that ^{the concentration of Burkholderia arboris was 1.0 × 10 6 cells / mL.} During the decomposition test, aeration stirring was performed so that the DO was 1.0 or more. The measurement and adjustment of DO and pH were also carried out in the same manner as in Test Example 1. The test solution was sampled over time, and the concentration of the n-Hex extract was measured according to JIS K 0102. The batch test was performed 3 times and the standard error was shown in the graph. The results are shown in FIG.

Test Example 6: Effect of input microbial concentration at the time of intermittent input A field demonstration tester originally designed and manufactured was installed at the wastewater treatment site of the factory. This demo tester consists of a raw water relay tank (50L), an oil decomposition tank (60L), an activated sludge tank (30L), a settling tank (12.5L), and a discharge relay tank (50L). It is drawn into the raw water relay tank and continuously flowed into the oil decomposition tank, activated sludge tank, and settling tank. Each of these tanks is connected to a discharge relay tank, and an arbitrary amount can be directly discharged from each tank. The treatment amount and residence time can be set for each tank, and an arbitrary amount of settled sludge can be returned from the settling tank to the activated sludge tank.

In the oil cracking tank, the temperature, pH, DO and MLSS are constantly monitored by the installed sensors. In addition, the foaming status is constantly monitored by the foaming sensor, and when foaming is detected, the defoaming agent is automatically added. When the pH is out of the set range, 2N sulfuric acid or 2N sodium hydroxide aqueous solution is automatically added from the pH adjustment tank to adjust the pH. Aeration is performed by supplying an amount of air adjusted by an oil decomposition tank flow meter and an activated sludge tank flow meter from the blower. The microbial preparation is pumped to the oil decomposition tank from a microbial preparation tank installed in the refrigerator at a set flow rate and time. Furthermore, a water sampling pump is attached to the oil cracking tank so that the required amount can be sampled at a specified date and time, and the liquid is sent to the water sampling tank in the refrigerator according to the setting.

A decomposition test in which the microbial preparation was intermittently added was carried out while the actual wastewater was continuously flowed to the demonstration tester. At the site, the microbial concentration at the time of intermittent injection was increased stepwise. As the microbial preparation, the same mixed preparation of Burkholderia alboris and Yarrowia lipolytica as in Test Example 1 was used. For the effluent samples from the oil and fat decomposition tank immediately after the elapse of the residence time on the 3rd and 5th days when the data was stable at the concentration of the input microorganisms at each input, the concentration of the n-Hex extract was adjusted according to JIS K 0102. It was measured and the effect of decomposing and removing oil was investigated. As a result, the measurement under the same conditions was performed twice (3rd day and 5th day), so that the reproducibility was confirmed.

Furthermore, at the time of sampling on the 5th day, the concentration of microorganisms in the effluent was measured, and the growth status of the input microorganisms was examined (graph ○ mark). The concentration of microorganisms was measured by real-time PCR targeting 16S ribosomal DNA of Berkholderia alboris for input microorganisms and by colony counting on LB medium for all microorganisms. Real-time PCR was performed 3 times for each sample, and total microbial concentration was measured by preparing 3 plates for each dilution step to determine the standard error. In addition, before increasing the microbial concentration, the supply of microorganisms was temporarily stopped for 3 days, and the effect on the n-Hex value was investigated. Under any condition, the pH of the fat decomposition tank was automatically adjusted to near neutral. The water temperature was between 25 and 35 ° C. In addition, during the treatment, aeration was stirred so that the DO was 1 mg / L or more. The n-Hex value was measured three times for each sample according to JIS K 0102, and the standard error was determined.

6-1. Results of low-concentration fats and oils (n-Hex value of about 300 mg / L) Wastewater treatment of 100 L / day on a scale of 1/1000 at the site where the level of n-Hex value is 300 mg / L level and the displacement is 100 tons / day. The test was performed at speed. The volume of treated water in the fat decomposition tank was set to 50 L, and the residence time was set to 12 hours. 5 × 10 ⁶ , 5 × 10 ⁷ , 1 × 10 ⁸ or 5 × 10 ⁸ cells / mL concentration of microbial preparation, 50 mL each, which is 1/1000 of the treated water volume, for 1 day to match the residence time. It was thrown in twice. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 5 × 10 ³ , 5 × 10 ⁴ , 1 × 10 ⁵ , 5 × 10 ⁵ cells / mL (x mark).

As a result, the concentration of the oil-degrading bacteria charged at the time of charging was 5 × 10 ⁴ cells / mL or more, and the n-Hex value was significantly reduced. When the addition of microorganisms was stopped (the concentration of microorganisms added at the time of addition was zero), the concentration of oil increased on the same day, but the decomposition of oil quickly recovered by re-injection. Despite the decomposition of fats and oils, no growth of 100 times or more of the introduced microorganisms was observed at any input amount. In addition, the concentration of the oil-degrading bacteria added at the time of addition was 1 × 10 ⁵ cells / mL, and no growth of the microorganism was observed, and the ^{concentration decreased at 5 × 10 5} cells / mL.

It is out of the conventional wisdom of biotechnology that the effect of decomposing fats and oils can be obtained even if microorganisms do not grow in culture, but the cause is that the concentration of fats and oils is not so high and there is a shortage of carbon sources for growth. it is conceivable that. It is probable that the oil could be sufficiently decomposed by the added concentration of microorganisms even if they did not grow. Therefore, it was found that it is useless to add a higher concentration of microorganisms than necessary.

In addition to the input microorganisms, microorganisms of ^{about 2 × 10 7} cells / mL (marked with △ in Fig. 6) originally exist in this wastewater, and even if the fat-decomposing microbial preparation is added, the total microbial concentration fluctuates greatly. There was no. The concentration of input microorganisms in the effluent is 1% or less of the total microbial concentration, and the decomposition effect can be exhibited even if the input microorganisms do not become dominant or major species. It deviates from common sense.

6-2. Results in drainage of medium-concentration fats and oils (n-Hex value of about 3000 mg / L) Treatment of 80 L / day on a scale of 1/1250 at the site where the level of n-Hex value is 3000 mg / L level and the displacement is 100 tons / day. The test was performed at speed. The volume of treated water in the fat decomposition tank was set to 60 L, and the residence time was set to 18 hours. 60 mL of the microbial preparation having a concentration of 5 × 10 ⁷ , 1 × 10 ⁸ , 5 × 10 ⁸ , 1 × 10 ⁹ cells / mL was added every 18 hours to match the residence time. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 5 × 10 ⁴ , 1 × 10 ⁵ , 5 × 10 ⁵ , 1 × 10 ⁶ cells / mL (x mark).

As a result, the input concentration of microorganisms during introduced is at 1 × ¹⁰ 5 cells / mL or more, n-Hex value has decreased significantly. When the addition of microorganisms was stopped (the concentration of microorganisms added at the time of addition was zero), the concentration of oil increased on the same day, but the decomposition of oil quickly recovered by re-injection. In addition, unlike normal microbial culture, even if the oil content is effectively decomposed, the added microorganisms do not grow by an order of magnitude, and conversely, the concentration of the added oil-degrading bacteria at the time of addition is 1 × 10 ⁶ cells / mL. At that time, the microbial concentration decreased. Since the concentration of fats and oils is not so high, it is considered that the cause is insufficient carbon source for growth. It is probable that the oil could be sufficiently decomposed by the added concentration of microorganisms even if they did not grow. Therefore, it was found that it is useless to add a higher concentration of microorganisms than necessary.

In addition to the input microorganisms, microorganisms of ^{about 8 × 10 7} cells / mL (marked with △ in Fig. 7) originally exist in this wastewater, and even if an oil-decomposed microbial preparation is added, the total microbial concentration fluctuates greatly. There was no. The concentration of input microorganisms in the effluent was 1% or less of the total microbial concentration, and the decomposition effect was sufficiently exhibited even if the input microorganisms did not become the dominant or major species.

6-3. Results in high-concentration fats and oils (n-Hex value about 10000 mg / L) drainage At the site where the level of n-Hex value is 30,000 mg / L level and the amount of drainage is 100 tons / day, the wastewater is diluted 3 times with groundwater and n. The test was carried out at a treatment rate of 80 L / day on a scale of 1/1250 with a −Hex value of about 10000 mg / L as diluted wastewater. The volume of treated water in the fat decomposition tank was set to 60 L, and the residence time was set to 18 hours. 60 mL of the microbial preparation having a concentration of 1 × 10 ⁸ , 5 × 10 ⁸ , 1 × 10 ⁹ , 3 × 10 ⁹ cells / mL was added every 18 hours to match the residence time. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 1 × 10 ⁵ , 5 × 10 ⁵ , 1 × 10 ⁶ , 3 × 10 ⁶ cells / mL (x mark).

As a result, the concentration of the added microorganisms at the time of charging was 5 × 10 ⁵ cells / mL or more, and the n-Hex value decreased by 95% or more. When the addition of microorganisms was stopped (the concentration of microorganisms added at the time of addition was zero), the concentration of oil increased on the same day, but the decomposition of oil quickly recovered by re-injection. In addition, unlike the normal culture of microorganisms, despite the decomposition of fats and oils, no growth of 100 times or more was observed as compared with the input microorganisms at any input amount. Furthermore, even if the oil was decomposed very effectively, no more than 10 times the growth of the introduced microorganisms was observed. In addition, a sufficient oil decomposition removal effect was obtained when the concentration of the added microorganisms at the time of addition was 1 × 10 ⁶ cells / mL, and there was almost no significance in adding more microorganisms.

In addition to the input microorganisms, microorganisms of ^{about 4 × 10 8} cells / mL (marked with △ in Fig. 8) originally exist in this diluted wastewater, and even if the fat-decomposing microbial preparation is added, the total microbial concentration is high. There was no change. The concentration of the input microorganisms in the effluent was about 1% or less of the total microbial concentration, and the decomposition effect was sufficiently exhibited even if the input microorganisms did not become the dominant species or the main species.

6-4. Results of ultra-high concentration fats and oils (n-Hex value of about 30,000 mg / L) at the site where the level of n-Hex value is 30,000 mg / L level and the displacement is 100 tons / day, the scale of 50 L / day is 1/2000. The test was performed at the processing speed. The volume of treated water in the fat decomposition tank was set to 50 L, and the residence time was set to 24 hours. 50 mL of the microbial preparation having a concentration of 5 × 10 ⁸ , 1 × 10 ⁹ , 3 × 10 ⁹ , 5 × 10 ⁹ , 1 × 10 ¹⁰ cells / mL was added every 24 hours to match the residence time. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 5 × 10 ⁵ , 1 × 10 ⁶ , 3 × 10 ⁶ , 5 × 10 ⁶ , 1 × 10 ⁷ cells / mL (x mark).

As a result, the concentration of the added microorganisms at the time of charging was 1 × 10 ⁶ cells / mL or more, and the n-Hex value was reduced by 99% or more. When the addition of microorganisms was stopped (the concentration of microorganisms added at the time of addition was zero), the concentration of oil increased on the same day, but the decomposition of oil quickly recovered by re-injection. Unlike normal culturing of microorganisms, despite decomposing fats and oils, no growth of 100 times or more was observed as compared with the introduced microorganisms at any input amount. Furthermore, even if the oil was decomposed very effectively, no more than 10 times the growth of the introduced microorganisms was observed. With growth levels comparable microorganisms by changing the concentration of charged microorganisms, it could only grow to 1 × 10 ⁷ cells / mL level at maximum. Therefore, it is useless to add more microorganisms.

In addition to the input microorganisms, microorganisms of 1 × 10 ⁹ cells / mL or more (marked with △ in Fig. 9) originally exist in this wastewater, and even if the fat-decomposing microbial preparation is added, the total microbial concentration fluctuates greatly. There was no. The concentration of input microorganisms in the effluent was 1% or less of the total microbial concentration, and the decomposition effect was sufficiently exhibited even if the input microorganisms did not become the dominant or major species.

Test Example 7: Effect of input microbial concentration at the time of input in continuous input A microbial preparation is continuously flowed while the same on-site demonstration tester as in Test Example 6 is installed at the wastewater treatment site of the factory. A disassembly test was conducted. At each site, the concentration of the supplied microorganisms was increased step by step every 3 days so that the concentration of the introduced microorganisms at the time of charging was in the range of 5 × 10 ³ to 1 × 10 ^{7 cells / mL.} As the microbial preparation, the same mixed preparation of Burkholderia alboris and Yarrowia lipolytica as in Test Example 1 was used, and the former microbial concentration was used as the total input microbial concentration.

The effluent was sampled on the 3rd day of each input microbial concentration, and the concentration of the n-Hex extract was measured according to JIS K0102 to examine the effect of decomposing and removing oil. In addition, the concentrations of the input microorganisms and all the microorganisms in the effluent were analyzed by the same method as in Test Example 6. Finally, the supply of the microbial preparation was stopped and the effect on the n-Hex value was investigated. Under any condition, the pH of the fat decomposition tank was automatically adjusted to near neutral. The water temperature was between 25 and 35 ° C. In addition, during the treatment, aeration was stirred so that the DO was 1 mg / L or more. The analysis of the n-Hex value was performed three times for each sample, and the standard error was determined.

7-1. Results of low-concentration fats and oils (n-Hex value of about 300 mg / L) Wastewater treatment of 100 L / day on a scale of 1/1000 at the site where the level of n-Hex value is 300 mg / L level and the displacement is 100 tons / day. The test was performed at speed. The volume of treated water in the fat decomposition tank was set to 50 L, and the residence time was set to 12 hours. Continuously feed microbial preparations at a concentration of 5 × 10 ⁶ , 5 × 10 ⁷ , 1 × 10 ⁸ or 5 × 10 ⁹ cells / mL at a supply rate of 4.17 mL / h, which is 1/1000 of the treated water flow rate. I put it in. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 5 × 10 ³ , 5 × 10 ⁴ , 1 × 10 ⁵ , 5 × 10 ⁵ cells / mL (x mark).

As a result, as in the case of intermittent charging, the concentration of the charged microorganisms at the time of charging was 5 × 10 ⁴ cells / mL or more, and the n-Hex value was significantly reduced. When the addition of microorganisms was stopped (the concentration of microorganisms added at the time of addition was zero), the oil concentration increased on the same day. Despite the decomposition of fats and oils, no growth of 100 times or more of the introduced microorganisms was observed at any input amount. In addition, the concentration of the added microorganisms at the time of addition was 1 × 10 ⁵ cells / mL, and no growth of microorganisms was observed, and the ^{concentration decreased at 5 × 10 5} cells / mL. Therefore, it was found that it is useless to add a higher concentration of microorganisms than necessary.

In addition to the input microorganisms, microorganisms of ^{about 2 × 10 7} cells / mL (marked with △ in Fig. 10) originally exist in this wastewater, and even if the fat-decomposing microbial preparation is added, the total microbial concentration fluctuates greatly. There was no. The concentration of the input microorganisms in the effluent was about 1% or less of the total microbial concentration, and the decomposition effect could be exhibited even if the input microorganisms did not become the dominant species or the main species.

7-2. Results in drainage of medium-concentration fats and oils (n-Hex value of about 3000 mg / L) Treatment of 80 L / day on a scale of 1/1250 at the site where the level of n-Hex value is 3000 mg / L level and the displacement is 100 tons / day. The test was performed at speed. The volume of treated water in the fat decomposition tank was set to 60 L, and the residence time was set to 18 hours. The microbial preparation having a concentration of 5 × 10 ⁷ , 1 × 10 ⁸ , 5 × 10 ⁸ , 1 × 10 ⁹ cells / mL is continuously added at a supply rate of 3.3 mL / h, which is 1/1000 of the treated water volume. did. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 5 × 10 ⁴ , 1 × 10 ⁵ , 5 × 10 ⁵ , 1 × 10 ⁶ cells / mL (x mark).

As a result, as in the case of intermittent turned-on microbial density during introduced is at 1 × ¹⁰ 5 cells / mL or more, n-Hex value has decreased significantly. When the addition of microorganisms was stopped (the concentration of microorganisms added at the time of addition was zero), the oil concentration increased on the same day. In addition, even if the oil was effectively decomposed, no extraordinary growth of the added microorganisms was observed, and conversely, the concentration of the added microorganisms at the time of addition was 1 × ^106.
At cells / mL, it did not grow at all. Therefore, it was found that it is useless to add a higher concentration of microorganisms than necessary.

In addition to the input microorganisms, microorganisms of ^{about 8 × 10 7} cells / mL (marked with △ in Fig. 11) originally exist in this wastewater, and even if the fat-decomposing microbial preparation is added, the total microbial concentration fluctuates greatly. There was no. The concentration of input microorganisms in the effluent was 1% or less of the total microbial concentration, and the decomposition effect was sufficiently exhibited even if the input microorganisms did not become the dominant or major species.

7-3. Results in high-concentration fats and oils (n-Hex value about 10000 mg / L) drainage At the site where the level of n-Hex value is 30,000 mg / L level and the amount of drainage is 100 tons / day, the wastewater is diluted 3 times with groundwater and n. The test was carried out at a treatment rate of 80 L / day on a scale of 1/1250 with a −Hex value of about 10000 mg / L as diluted wastewater. The volume of treated water in the fat decomposition tank was set to 60 L, and the residence time was set to 18 hours. The microbial preparation having a concentration of 1 × 10 ⁸ , 5 × 10 ⁸ , 1 × 10 ⁹ , 3 × 10 ⁹ cells / mL is continuously added at a supply rate of 3.3 mL / h, which is 1/1000 of the treated water volume. did. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 1 × 10 ⁵ , 5 × 10 ⁵ , 1 × 10 ⁶ , 3 × 10 ⁶ cells / mL (x mark).

As a result, as in the case of intermittent turned-on microbial density during turned is at 5 × ¹⁰ 5 cells / mL or more, n-Hex value has decreased by more than 95%. When the addition of microorganisms was stopped (the concentration of microorganisms added at the time of addition was zero), the oil concentration increased on the same day. In addition, unlike the normal culture of microorganisms, despite the decomposition of fats and oils, no growth of 100 times or more was observed as compared with the input microorganisms at any input amount. Furthermore, even if the oil was effectively decomposed, the growth of more than 10 times that of the introduced microorganism was not observed. In addition, the concentration of oil-degrading bacteria added at the time of addition is 1 × 10 ⁶
Sufficient oil decomposition and removal effect was obtained with cells / mL, and the significance of adding more microorganisms was hardly recognized.

Also, during this dilution waste water, in addition to charged microorganisms originally present 4 × 10 ⁸ cells / mL of about microorganisms (Figure 12 △ mark), it is charged with oil degrading microorganism formulation, significant to the total concentration of microorganisms There was no change. The concentration of the input microorganisms in the effluent was about 1% or less of the total microbial concentration, and the decomposition effect was sufficiently exhibited even if the input microorganisms did not become the dominant species or the main species.

7-4. Results of ultra-high concentration fats and oils (n-Hex value of about 30,000 mg / L) at the site where the level of n-Hex value is 30,000 mg / L level and the displacement is 100 tons / day, the scale of 50 L / day is 1/2000. The test was performed at the processing speed. The volume of treated water in the fat decomposition tank was set to 50 L, and the residence time was set to 24 hours. Microbial preparations at a concentration of 5 × 10 ⁸ , 1 × 10 ⁹ , 3 × 10 ⁹ , 5 × 10 ⁹ , 1 × 10 ¹⁰ cells / mL were continuously added at a feed rate of 2.1 mL / h. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 5 × 10 ⁵ , 1 × 10 ⁶ , 3 × 10 ⁶ , 5 × 10 ⁶ , 1 × 10 ⁷ cells / mL (x mark).

As a result, as in the case of intermittent charging, the concentration of the charged microorganisms at the time of charging was 1 × 10 ⁶ cells / mL or more, and the n-Hex value decreased by 99% or more. When the addition of microorganisms was stopped (the concentration of microorganisms added at the time of addition was zero), the oil concentration increased on the same day. Unlike normal culturing of microorganisms, despite decomposing fats and oils, no growth of 100 times or more was observed as compared with the introduced microorganisms at any input amount. Furthermore, even if the oil was effectively decomposed, the growth of more than 10 times that of the introduced microorganism was not observed. With growth levels comparable microorganisms by changing the concentration of charged microorganisms, it could only grow to 1 × 10 ⁷ cells / mL level at maximum. Therefore, it is useless to add more microorganisms.

In addition to the input microorganisms, microorganisms of ^{about 1 × 10 9} cells / mL or more (marked with Δ in FIG. 13) are originally present in this wastewater, and even if the fat-decomposing microbial preparation is added, the total microbial concentration is high. There was no change. The concentration of input microorganisms in the effluent was 1% or less of the total microbial concentration, and the decomposition effect was sufficiently exhibited even if the input microorganisms did not become the dominant or major species.

Test Example 8: Effect of residence time A decomposition test was conducted in which a microbial preparation was intermittently added while continuously flowing wastewater having a low, medium, high, and very high oil concentration (n-Hex value). The same on-site demonstration demonstration tester as in Test Example 6 was installed at the site and the test was conducted. The residence time was gradually increased from 4 hours to 24 hours with respect to the treated water volume of 60 L in the oil / fat decomposition tank, and a microbial preparation having a concentration corresponding to the oil / fat concentration was added for each residence time. Therefore, the processing speed was gradually reduced from 360 L / day to 60 L / day. As the microbial preparation, the same mixed preparation of Burkholderia alboris and Yarrowia lipolytica as in Test Example 1 was used.

After the residence time had elapsed, the effluent was sampled immediately before the next microbial preparation was added, and the concentration of the n-Hex extract was measured according to JIS K0102 to examine the effect of decomposing and removing oil. The pH of the fat decomposition tank was automatically adjusted to near neutral. The water temperature was between 25 and 35 ° C. In addition, during the treatment, aeration was stirred so that the DO was 1 mg / L or more. The analysis of the n-Hex value was performed three times for each sample, and the standard error was determined.

8-1. Results of low-concentration fats and oils (n-Hex value about 300 mg / L) drainage At the site where the level of n-Hex value is 300 mg / L level and the displacement is 100 tons / day, the actual wastewater is continuously poured into the demonstration tester. However, the test was conducted. At the beginning of each set residence time, ^{60 mL of microbial preparation having a concentration of 5 × 10 7} cells / mL was added, which is 1/1000 of the treated water flow rate. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 5 × 10 ⁴ cells / mL. The n-Hex value decreased by nearly 90% after a residence time of 12 hours. Furthermore, the n-Hex value decreased by 90% or more after the residence time of 18 hours, and achieved the discharge standard value of less than 30 mg / L to the sewerage of many local governments. The treatment effect was such that even the activated sludge treatment, which is a treatment, became unnecessary.

8-2. Results of drainage of medium-concentration fats and oils (n-Hex value of about 3000 mg / L) At the site where the level of n-Hex value is 3000 mg / L level and the displacement is 100 tons / day, the actual wastewater is continuously poured into the demonstration tester. However, the test was conducted. At the beginning of each set residence time, ^{60 mL of microbial preparation having a concentration of 5 × 10 8} cells / mL was added, which is 1/1000 of the treated water flow rate. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 5 × 10 ⁵ cells / mL. The n-Hex value decreased by 95% or more in 18 hours, 98% or more in 20 hours, less than 50 mg / L, and 99% or more in 24 hours. The value was less than 30 mg / L.

8-3. Results of drainage of high-concentration fats and oils (n-Hex value of about 10000 mg / L) At the site where the level of n-Hex value is 30,000 mg / L level and the displacement is 100 tons / day, the wastewater is diluted three times with groundwater. The test was carried out while continuously flowing through the demo tester. At the beginning of each set residence time, ^{60 mL of microbial preparation having a concentration of 1 × 10 9} cells / mL was added, which is 1/1000 of the treated water flow rate. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 1 × 10 ⁶ cells / mL. When the residence time was 20 hours or more, the n-Hex value decreased by 99% or more, and in 24 hours, it decreased to less than 30 mg / L, which is the standard value for discharge to the sewer of many local governments.

8-4. Results of ultra-high concentration fats and oils (n-Hex value about 30,000 mg / L) drainage At the site where the level of n-Hex value is 30,000 mg / L level and the displacement is 100 tons / day, the actual wastewater is continuously used as a demonstration tester. The test was carried out while flowing. At the beginning of each set residence time, ^{60 mL of microbial preparation having a concentration of 3 × 10 9} cells / mL was added, which is 1/1000 of the treated water flow rate. The results are shown in FIG. The concentration of the added microorganisms at the time of charging is 3 × 10 ⁶ cells / mL. The n-Hex value decreased by 99% or more when the residence time was 24 hours.

Test Example 9: Relationship between the amount of inflow oil and the amount of input microorganisms Similar to Test Example 6, wastewater treatment of a plurality of oil amounts was performed, and the relationship between the amount of inflow oil and the amount of input microorganisms was examined. The relationship between the amount of inflowing oil and the amount of input microorganisms is shown below.

＊ノルマルヘキサン値から算出される油分量
表１の結果から、油脂分解槽に投入される微生物製剤の量は、油脂分解槽に流入する油脂含有排水中のノルマルヘキサン抽出物１ｍｇ当たり、３．０×１０^４〜１．０×１０^８ ｃｅｌｌｓ、好ましくは３．０×１０^４〜１×１０^７ｃｅｌｌｓほどで十分な油脂分解が達成されることが明らかになった。

* Oil content calculated from the normal hexane value From the results in Table 1, the amount of the microbial preparation charged into the fat decomposition tank is 3.0 per 1 mg of the normal hexane extract in the oil-containing wastewater flowing into the fat decomposition tank. It was clarified that sufficient oil and fat decomposition was achieved in about × 10 ^{4 to} 1.0 × 10 ⁸ cells, preferably about 3.0 × 10 ⁴ to 1 × 10 ^{7 cells.}

Claims (1)

The invention described in a part of this specification.

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